Table 1.
Characteristics of the development and validation study populations
| Characteristic | Development(n = 7685) | Validation(n = 7696) | P |
|---|---|---|---|
| Demographics | |||
| age (yr; mean [SD]) | 61.6 (15.7) | 61.2 (15.6) | 0.20 |
| male (%) | 55 | 55 | 0.70 |
| black race/ethnicity (%) | 32 | 33 | 0.36 |
| Time on dialysis (yr; mean [SD]) | 2.1 (3.3) | 2.2 (3.3) | 0.35 |
| Cause of renal disease (%) | 0.43 | ||
| diabetes | 38 | 38 | |
| glomerular diseases | 9 | 9 | |
| hypertension | 26 | 27 | |
| other | 27 | 26 | |
| Access type (%) | 0.68 | ||
| fistula | 23 | 23 | |
| graft | 33 | 34 | |
| catheter | 39 | 37 | |
| missing/unknown | 5 | 6 | |
| Comorbid conditions (%) | |||
| diagnosis of coronary artery disease | 41 | 40 | 0.58 |
| diagnosis of CHF with hospitalization in past 12 mo | 20 | 21 | 0.96 |
| myocardial infarction ever | 20 | 20 | 0.91 |
| absence of hypertension | 16 | 16 | 0.98 |
| diabetes requiring insulin | 35 | 35 | 0.92 |
| history of cerebrovascular accident | 6 | 6 | 0.52 |
| history of PVD | 24 | 24 | 0.64 |
| amputation as a result of PVD | 7 | 7 | 0.79 |
| gastrointestinal bleeding | 8 | 8 | 0.95 |
| ascites in past 12 mo | 1 | 2 | 0.80 |
| diagnosis of hepatitis B | 1 | 1 | 0.69 |
| diagnosis of hepatitis C | 5 | 5 | 0.84 |
| malignancy ever | 12 | 11 | 0.02 |
| HIV/AIDS | 1 | 2 | 0.01 |
| depression | 20 | 20 | 0.98 |
| dementia | 5 | 5 | 0.47 |
| substance abuse in past 12 mo | 4 | 4 | 0.50 |
| recurrent cellulitis, skin infection, gangrene | 10 | 10 | 0.34 |
| COPD | 12 | 13 | 0.74 |
| use of home oxygen | 5 | 5 | 0.50 |
| vasculitis | 2 | 2 | 0.96 |
| nursing home resident | 8 | 8 | 0.41 |
| inability to transfer | 25 | 24 | 0.16 |
| wheelchair bound | 21 | 19 | 0.09 |
| Laboratory/physiologic parameters (%) | |||
| albumin (g/dl; median [IQR]) | 3.7 (3.3 to 4.0) | 3.7 (3.3 to 4.0) | 0.18 |
| phosphorous (mg/dl; median [IQR]) | 5.4 (4.4 to 6.6) | 5.4 (4.4 to 6.7) | 0.05 |
| hemoglobin (g/dl; median [IQR]) | 10.5 (8.8 to 11.8) | 10.6 (9.0 to 11.8) | 0.03 |
| SBP (mmHg; median [IQR]) | 149 (133 to 166) | 151 (134 to 167) | 0.06 |
| BMI (kg/m2; median [IQR]) | 25.1 (21.7 to 29.6) | 25.1 (21.7 to 29.7) | 0.85 |
BMI, body mass index; COPD, chronic obstructive pulmonary disease; IQR, interquartile range; SBP, systolic BP.